Device for securing arcuate stereotype pringing plates onto a plate cylinder of web-fed rotary printing presses

ABSTRACT

The invention relates to a device for securing arcuate stereotype printing plates forming a part of a circle and being secured onto a plate cylinder of web-fed rotary printing presses by tensioning several pairs of viselike underside jaws actuating resiliently in an axial direction one against another and gripping into underside facets of the plate. The jaws are shaped like segments forming a part of a circle and corresponding to the length of curvature of the plate. The stereotype plates are positioned on supporting segments which are secured onto the body of the cylinder and correspond to the length of curvature of the plate. The jaws are provided with a thread on their respective underside. A threaded segment meshes with the thread of the jaw and has teeth on its underside which coact with a pinion being secured on an axle which is arranged parallel to the axis of the plate or form cylinder, the axle of which is driven by a worm gear. By actuating the worm gear the jaws are shifted and the printing plate is clamped. The worm of the worm gear is preloaded in the axial direction by cup springs bundled as a package. In order to clamp four plates on the circumference of the plate cylinder, the threaded jaw segment 34 has a radian length of 90* and the toothed segment 46 has a thread on its upper side and a length of 60* of radian measure, the maximum of the clamping way i.e. the difference between 90* and 60*, amounts therefore to 30* of radian measure.

United States Patent I I I [52] US. Cl ll/378, 101/415.1 [51] Int. Cl B411 13/16, B4lf27/06 [50] Field of Search 101/378, 415.1

[56] References Cited UNITED STATES PATENTS 1,994,384 3/1935 Bradshaw l0l/378 2,190,380 2/1940 Horton 101/378 2,642,800 6/1953 Crabtree 101/378 2,709,405 /1955 McWhorter.. 101/378 2,893,319 7/1959 Ziebell 101/378 2,965,024 12/1960 Ziebell 101/378 3,001 ,472 9/1961 Parrish 101/378 Inventors Hans-Bernhard Bolza-Schunemann Wurzburg; Heinrich Lichtblau, Karlstadt, both of Germany Appl. No. 866,211 Filed Oct. 14, 1969 Patented Dec. 7, 1971 Assignee Schnellpre ssenfabrik Koenig & Bauer Aktiengesellschaft Wurzburg, Germany Priority June 1 l, 1969 Germany P 19 29 604.4

DEVICE FOR SECURING ARCUATE STEREOTYPE PRINTING PLATES ONTO A PLATE CYLINDER OF WEB-FED ROTARY PRINTING PRESSES Claims, 10 Drawing Figs.

3,020,842 2/1962 Neal....-. 10I/4l5.l

3,195,457 7/1965 Luehrs l0I/378 X 3,478,778 1/1970 Muth et al. l0I/378 FOREIGN PATENTS 224,467 10/1959 Australia I0l/4l5.l

Primary Examiner-Clyde I. Coughenour Attorney-Jones and Lockwood ABSTRACT: The invention relates to a device for securing arcuate stereotype printing plates forming a part of a circle and being secured onto a plate cylinder of web-fed rotary printing presses by tensioning several pairs of viselike underside jaws actuating resiliently in an axial direction one against another and gripping into underside facets of the plate. The jaws are shaped like segments forming a part of a circle and corresponding to the length of curvature of the plate. The stereotype plates are positioned on supporting segments which are secured onto the body of the cylinder and correspond to the length of curvature of the plate. The jaws are provided with a thread on their respective underside. A threaded segment meshes with the thread of the jaw and has teeth on its underside which coact with a pinion being secured on an axle which is arranged parallel to the axis of the plate or form cylinder, the axle of which is driven by a worm gear. By actuating the worm gear the jaws are shifted and the printing plate is clamped. The worm of the worm gear is preloaded in the axial direction by cup springs bundled as a package. In order to clamp four plates on the circumference of the plate cylinder, the threaded jaw segment 34 has a radian length of 90 and the toothed segment 46 has a thread on its upper side and a length of of radian measure, the maximum of the clamping way ie the difference between and 60, amounts therefore to 30 of radian measure.

PATENTED DEB 71971 SHEET 0 3 0F 10 PATENTEU DEC 7 l9?! SHEET 0 4 OF 10 PATENTEBHEE 71971 3.625150 SHEEI 050F10 Fig. 5

PATENTEUDEC mm 3.625150 sum 10m 10 HY. M

PRINGING PLATES ONTO A PLATE CYLINDER OF WEB- FED ROTARY PRINTING PRESSES BACKGROUND OF THE INVENTION A clamping device has been known as disclosed in the copending US. Pat. No. 3,487,778 application of Gregor Nikolaus Muth and Heinrich Lichtblau, Ser. No. 732,591, filed May 28, 1968 and assigned to the same assignee which shows clamping jaws like the present invention. It is highly suited to clamp plates on the plate cylinder in such a manner that the deformation of the plates by the centrifugal forces is reduced to a degree unknown up to now.

However, in this disclosure there is not shown what is to be done in order to clamp six plates along the length and four plates on the circumference of the plate cylinder.

In the referred to patent application spacing rods are used for transmitting the clamping movement from a threaded spindle to the clamping jaws. With this great number of plates the danger arises that said spacing rods which transmit the clamping forces would buckle because of the necessary length. The semicircular collars in this prior apparatus by which the forces coming from the tensioning screws are transmitted to the spacing rods take up a great deal of space in axial direction because the semicircular collars have to be multiplied. Besides this it is disadvantageous to provide the spacing rods in the plate-clamping system, because the supporting segments and the clamp segments would be unsymmetrical and not fully exchangeable.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a device for clamping six plates along the length and four plates on the circumference of the plate cylinder. The actuating device has to move the clamping elements parallelly to one another in a high degree of accuracy and has to be as adjacently close to the seats of the plates as possible.

The actuating device should be power driven and not manually.

It is the further object of the invention to provide the plateclamping systems in such a manner in view of the commercial manufacturing of these cylinders, that the clamping systems can be mounted in each position, being staggered by 30, e.g., the grooves between the leading and the trail edges of the plates should be selectable in jumps or steps of 30.

Experience has taught that after a certain running time of the rotary printing press the clamps dig into the plate bevels due to the impacts resulting from the printing pressure. In case of a rigid locking device this results in the holding strength of the clamps to the plate decreasing and is even becoming nonexistent in extreme cases. It is therefore also an object of the invention to eliminate this problem.

BRIEF DESCRIPTION OF THE DRAWINGS An embodiment of the invention will now be described by way of example with reference to the accompanying drawings but it is to be clearly understood that the invention is by no means restricted to the details of this embodiment.

FIG. I shows an unrolling of the plate cylinder having mounted plates,

FIG. 2 is a longitudinal cross section through the clamping device along the line II-II in FIG. 3 on an enlarged scale,

FIG. 3 is an unrolling of the clamping device, it is shown as a cross section along the line III-III in FIG. 2,

FIG. 4 shows an end view of the plate cylinder,

FIG. 5 is a fragmentary cross section along the line V-V in FIG. 4 on an enlarged scale,

FIG. 6 shows a fragmentary cross section along the line VI-VI in FIG. 4 on an enlarged scale,

FIG. 7 is a top plan view of the torque producing source,

FIG. 8 shows a variation of the plate arrangement on the cylinder,

FIG. 9 shows an enlarged fragmentary view along the line IXIX in FIG. 4, and

FIG. 10 is a perspective view of one end of the form cylinder showing the angular relationship of a threaded jaw segment, its threaded segment piece meshing with it and the drive gearing.

DESCRIPTION OF THE PREFERRED EMBODIMENT Twenty-four stereotype printing plates 2 to 25 are clamped on a fonn cylinder 1. One half of the plates 2 to 25 is clamped from the right hand and the other half from the left hand end of the form cylinder 1. Supporting segments 27, 28, 29 are secured on a main body 26 of the form cylinder 1, these segments support a plate 3 at its under side, as shown by way of example in FIG. 2. The plates 2 to 25 are provided with circumferentially extending clamping grooves 30 along the whole length of their underside in which grip the jaws of jaw segments 31 to 34.

Segments 31, 32 and 33, 34 respectively of the jaw segments have their jaws extending towards each other and act in pairs to grip the stereotype plate 3 viselike and hold it on the supporting segments 27, 28, 29. The jaw segments are guided by the main body 26 and the supporting segments 27 to 29. The jaw segment 34 is actuated by a fastening mechanism from outside. The force actuated from outside on the jaw segment 34 is transmitted to one part of the stereotype plate 3 by one part of jaw segment 34 and by the other part 34a, see FIG. 3, by the jaw segment 32 through spaced rods 35 threadedly attached at one end to jaw segments 34 and 34a Between the jaw segment 32 and the spaced rods 35 there are provided packages of cup springs 36 which permit a certain length compensation of the fastening movement of the jaw segment 32. These cup spring packages are made up of a spring in an openended cavity in a face of the jaw segment with a rod having a reduced portion passing through the spring, one end of the spring pressing against the bottom of the cavity while a shoulder formed by the larger and smaller rod portions presses against the other end of the spring. A circular and enlarged end plate 37 is attached to the inboard end of rod 35 by a screw and rides against its adjacent jaw segment.

When the plate 3 is being removed the spaced rods 35 are stressed by tension and the end plates 37 pull against their adjacent jaw segment. The jaw segment 31 and by this the stereotype plate 3 can be shifted by screws 38 in axial direction. The threads 38a of the screws 38, see FIG. 3, screws into threaded bores 28a of the supporting segment 28. The force of the screws 38 is transmitted by end surfaces 39 of their heads 40 to the adjacent supporting segment 31 for the purpose of registering in lateral direction. The jaw segment 31 is preloaded permanently by the pressure spring 41 housed in an open-ended cavity 31a in'a face of jaw segment 31. The spring 41 imparts a pressure against the head 40 of the screw 38. The movement of the screw 38 is transferred to the end of rod 42 abutting against the end of screw 38. Rod 42 has a shoulder thereon which presses against a cup spring 43 in jaw segment 33 through which the rod extends in such a manner that the jaw segment moves in the same direction as the jaw segment 31.

By this advantageous solution of the mounting the printing plates 2 to 25 can be clamped on the fonn cylinder 1 also in another arrangement in steps of 30 as viewed in the circumferential direction. These rearrangements can be carried out without drilling new fastening holes for the supporting segments 27 to 29 or without making other respective alternations in the main body 26 of the form cylinder 1.

The stereotype plate 3 can be shifted in circumferential direction by screws 44, see FIG. 3, which screw into the support segments 27 to 29 in the circumferential direction. The heads of these screws 44 contact the ends of the plate. One of the screws 44 actuates against the middle of one end of the plate and the other two actuate against the other plate end. The same arrangement applies for the other plates.

The same support segments 27 to 29 and jaw segments 31 to 34 can be used for all plates 2 to 25 which have to be fastened onto the form cylinder 1 except the supporting segment 45,

see FIG. 5, which is used on the ends of the form cylinder 1 instead of a supporting segment 27.

The jaw segment 34, see FIG. 5, is moved by a threaded segment piece 46 movably mounted in a circumferential recess in the outer surface of main body 26 which mates by means of a flat thread 47 thereon into a flat thread 48 provided on the underside of the jaw segment 34.

The threaded segment piece 46 is shifted in circumferential direction by a pinion 49 meshing by its toothing with the inner toothing 50 being provided on the underside of the threaded segment piece 46.

The pinion 49 is secured on the axle 51 which is joumaled in a bore 52 of the main body 26 by means of the bearings 53 and is driven by a wonn 54, see FIGS. 4, and 9 and a worm gear 55. The worm 54 is rigidly connected to the axle 56 joumaled in the housing 57 which is secured to the frontal end 58 of the main body 26.

The worm 54 is axially preloaded by the springs 59, see FIG. 9, mounted so as to urge the worm 54 against the worm gear 55. If the jaws dig into the stereotype plate the jaw segments 32 and 34 can eliminate the decreasing of the fastening strength by means of the cup springs 59. However, this automatically is effected not by turning, but by shifting the worm 54 in axial direction.

FIG. 6 shows how the axle 51 is arranged under the plates 2 and 3 in the bore 52 extending in the axial direction in the main body 26 and according to the FIG. 2 or 5 so that the threaded segment piece 46 associated with plate 4 can be moved.

Any overloading of the fastening and clamping device can be avoided by tensioning manually by means of a torque wrench or mechanically by a motor which is connected to a slipping clutch having a predetermined torque.

In FIG. 7 is shown an automatically working tensioning and dismounting device. A housing 57 is secured on the frontal end 58 of the plate cylinder 1 on which the printing plates 2 to 25 are fastened. The worm 54 secured on the axle 56 is journaled in the housing 57.

The torque source 60 being limitable in the amount is provided in production to be in alignment with the axis of the axle 56 and is secured to the frame of the printing press, for example, on the frame ll. It is controlled by three pushbuttons 61 to 63. The desired rotating direction can be set up by the pushbuttons 62, 63. By pushing these buttons an axial movement of the driving shaft 64 of the torque source is initiated. The head of driving shaft 64 is provided with an internal wrenching fitting which fits with a socket head on the axle 56.

The right position of the axle 56 in respect to aligning it with the torque source 60 can be found by rotating the form cylinder 1 with drawn-in speed. lts rotating is stopped by the path button 61.

FIG. 8 shows a variation of the plate arrangement for a form cylinder running in the opposite direction to the form cylinder 1. This brings about a rearrangement of the plate 2 to 25, and of the plate-fastening systems like a reflected image is possible. The same parts 27, 28 to 29 and 31 to 34 can be used.

By the solution according to the invention a fastening device is provided which effects a highly accurate, parallel guiding of the jaw segment and guarantees a very good transmission of the forces and always the same predetermined tension force. By means of the mechanical torque source a quick tensioning is possible without any strain of the operator.

Although the jaws dig into the plate a permanently continuous tension force is reached by automatic tensioning.

According to the present invention the components of the stereotype plate-fastening device are the same for all 24 plates.

Numerous variations of the plate arrangement can be achieved by only mounting the plates in a manner according to the desired purpose without it being necessary to alter the components or the main body of the cylinder.

What is claimed is:

1. Device for securing arcuate stereotype printing plates forming part of a circle and having in their underside circumferential extending clamping grooves and being secured onto a plate cylinder of webfed rotary printing presses by tensioning several pairs of viselike underside jaw segments biased in axial direction against one another, said jaw segments corresponding in arcuate length to that of the plate, said stereotype plate being positioned on supporting segments which are secured onto the body of the cylinder and correspond to the curvature of the plate, one of said jaw segments (34) being provided with a thread (48) on its underside and being moved into a clamping position by means of a threaded segment piece (46) having threads mating in said jaw segment thread (48), said threaded segment piece (46) being slidably moved by means of a pinion (49) mating in teeth (50) on the threaded segment piece (46) and being secured on a tumable shaft (51) being arranged parallel to the axis of the cylinder and having wormgearing means (54, 55) mounted on a cylinder end (58), said worm-gearing means havinga worm gear (55) on said pinion turnable shaft and a worm gear drive worm (54), said drive worm having spring means (59) preloading the worm in its axial direction.

2. Device corresponding to claim 1 wherein the plate is tensioned and released by a torque source having limitable means in respect of the measure of the torque.

3. Device corresponding to claim 1 wherein the jaw segments have a radian length of and the threaded segment piece a radian length of 60 by means of which the clamping way amounts to 30 of radian measure.

4. Device corresponding to claim 3 wherein the stereotype plates are staggerable in pairs so that the web is guided by four plates at least in each position of the form cylinder.

5. Device corresponding to claim 1 wherein the stereotype plates are staggerable in pairs so that the web is guided by four plates at least in each position of the form cylinder.

6. Mechanism for securing arcuate stereotype printing plates forming part of a circle on a plate cylinder of web-fed rotary printing presses comprising, in combination, supporting segments secured onto the body of the cylinder and corresponding to the curvature of the plates, a plurality of pairs of viselike underside jaws for clamping the plates mounted by said support segments, resilient tensioning means acting in the axial direction on said jaws which act against one another, said jaws being shaped like segments forming part of a circle and corresponding in arcuate length to that of the plates, one of said jaw segments being provided with a thread on its underside and being moved into a clamping position by means of a threaded segment piece mating in said jaw segment thread and slidably mounted in a circumferential peripheral recess in said cylinder, said threaded segment piece being slidably moved by means of a pinion mating in teeth on said threaded segment piece, said pinion being secured on a rotatable shaft mounted parallel to the axis of the cylinder and having worm-gearing means mounted on a cylinder end, said worm-gearing means 7 having a worm gear on said pinion rotatable shaft and a worm gear drive worm, said drive worm having spring means preloading the worm axially.

7. Device corresponding to claim 6 wherein the plate is tensioned and released by a torque source having limitable means in respect of the measure of the torque.

8. Device corresponding to claim 6 wherein the jaw segments have a radian length of 90 and the threaded segment piece a radian length of 60 by means of which the clamping way amounts to 30 of radian measure.

9. Device corresponding to claim 8 wherein the. stereotype plates are staggerable in pairs so that the web is guided by four plates at least in each position of the form cylinder.

10. Device corresponding to claim 6 wherein the stereotype plates are staggerable in pairs so that the web is guided by four plates at least in each position of the form cylinder. 

1. Device for securing arcuate stereotype printing plates forming part of a circle and having in their underside circumferential extending clamping grooves and being secured onto a plate cylinder of web-fed rotary printing presses by tensioning several pairs of viselike underside jaw segments biased in axial direction against one another, said jaw segments corresponding in arcuate length to that of the plate, said stereotype plate being positioned on supporting segments which are secured onto the body of the cylinder and correspond to the curvature of the plate, one of said jaw segments (34) being provided with a thread (48) on its underside and being moved into a clamping position by means of a threaded segment piece (46) having threads mating in said jaw segment thread (48), said threaded segment piece (46) being slidably moved by means of a pinion (49) mating in teeth (50) on the threaded segment piece (46) and being secured on a turnable shaft (51) being arranged parallel to the axis of the cylinder and having worm-gearing means (54, 55) mounted on a cylinder end (58), said worm-gearing means having a worm gear (55) on said pinion turnable shaft and a worm gear drive worm (54), said drive worm having spring means (59) preloading the worm in its axial direction.
 2. Device corresponding to claim 1 wherein the plate is tensioned and released by a torque source having limitable means in respect of the measure of the torque.
 3. Device corresponding to claim 1 wherein the jaw segments have a radian length of 90* and the threaded segment piece a radian length of 60* by means of which the clamping way amounts to 30* of radian measure.
 4. Device corresponding to claim 3 wherein the stereotype plates are staggerable in pairs so that the web is guided by four plates at least in each position of the form cylinder.
 5. Device corresponding to claim 1 wherein the stereotype plates are staggerable in pairs so that the web is guided by four plates at least in each position of the form cylinder.
 6. Mechanism for securing arcuate stereotype printing plates forming part of a circle on a plate cylinder of web-fed rotary printing presses comprising, in combination, supporting segments secured onto the body of the cylinder and corresponding to the curvature of the plates, a plurality of pairs of viselike underside jaws for clamping the plates mounted by said support segments, resilient tensioning means acting in the axial direction on said jaws which act against one another, said jaws being shaped like segments forming part of a circle and corresponding in arcuate length to that of the plates, one of said jaw segments being provided with a thread on its underside and being moved into a clamping position by means of a threaded segment piece mating in said jaw segment thread and slidably mounted in a circumferential peripheral recess in said cylinder, said threaded segment piece being slidably moved by means of a pinion mating in teeth on said threaded segment piece, said pinion being secured on a rotatable shaft mounted parallel to the axis of the cylinder and having worm-gearing means mounted on a cylinder end, said worm-gearing means having a worm gear on said pinion rotatable shaft and a worm gear drive worm, said drive worm having spring means preloading the worm axially.
 7. Device corresponding to claim 6 wherein the plate is tensioned and released by a torque source having limitable means in respect of the measure of the torque.
 8. Device corresponding to claim 6 wherein the jaw segments have a radian length of 90* and the threaded segment piece a radian length of 60* by means of which the clamping way amounts to 30* of radian measure.
 9. Device corresponding to claim 8 wherein the stereotype plates are staggerable in pairs so that the web is guided by four plates at least in each position of the form cylinder.
 10. Device corresponding to claim 6 wherein the stereotype plates are staggerable in pairs so that the web is guided by four plates at least in each position of the form cylinder. 